Constructing Four-Membered Heterocycles by Cycloisomerization

ACS Catalysis, Год журнала: 2023, Номер 13(7), С. 4101 - 4110

Опубликована: Март 10, 2023

Four-membered heterocycles are highly sought after in modern drug discovery as they provide beneficial properties to the target molecules. Despite tremendous efforts by synthetic research community, there is a need for simple and new method incorporate these motifs into design Herein, we reveal cycloisomerization strategy construction of oxetane azetidine rings via metal hydride hydrogen atom transfer/radical polar crossover, which challenging both enthalpically entropically. This suitable synthesizing polysubstituted four-membered heterocycles. mild functional-group tolerant reaction has broad substrate scope, including spiro structure, an important motif research. Various heterocyclic building blocks can be synthesized product derivatization. We also discuss mechanism, focusing on ring formation, deuterium experiments DFT studies.

Язык: Английский

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Cobalt-catalyzed HAT reaction for asymmetric hydrofunctionalization of alkenes and nucleophiles

Chem Catalysis, Год журнала: 2023, Номер 3(3), С. 100526 - 100526

Опубликована: Фев. 13, 2023

Язык: Английский

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Photoinduced Cobalt Catalysis for the Reductive Coupling of Pyridines and Dienes Enabled by Paired Single‐Electron Transfer**

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(45)

Опубликована: Сен. 7, 2023

Abstract Selective hydroarylation of dienes has potential to provide swift access useful building blocks. However, most existing methods rely on stabilised by an aromatic group and transmetallation or nucleophilic attack steps require electron‐rich aryl coupling partners. As such, there are few examples which tolerate wide‐spread heteroarenes such as pyridine. Whilst allylic C−H functionalisation could be considered alternative approach, the positional selectivity unsymmetrical substrates is hard control. Here, we report a general approach for selective hydropyridylation under mild conditions using metal catalysed hydrogen‐atom transfer. Photoinduced, reductive enable simultaneous formation cobalt‐hydride catalyst persistent radical easily‐synthesised pyridyl phosphonium salts. This facilitates in traceless manner at C4‐position wide‐range pyridine substrates. The mildness method underscored its functional‐group tolerance demonstrated applications late‐stage functionalisation. Based combination experimental computational studies, propose mechanistic pathway proceeds through non‐reversible transfer (HAT) from cobalt hydride species uniquely presence other olefins due much higher relative barrier associated with olefin HAT.

Язык: Английский

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Thiyl Radical Trapped by Cobalt Catalysis: An Approach to Markovnikov Thiol–Ene Reaction

Organic Letters, Год журнала: 2024, Номер 26(3), С. 591 - 596

Опубликована: Янв. 12, 2024

In the presence of a thiyl radical species, catalytic Markovnikov thiol–ene reaction is challenging because it prefers to proceed via pathway, thereby leading anti-Markovnikov selectivity. this work, rare example engaged in enabled by cobalt catalysis reported. This protocol features avoidance unique oxidants, exclusive regioselectivity, and broad substrate scope. Scalable synthesis late-stage modification complex molecules demonstrate practicability protocol.

Язык: Английский

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Cobalt-Catalyzed Carbon–Heteroatom Transfer Enables Regioselective Tricomponent 1,4-Carboamination

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(12), С. 8508 - 8519

Опубликована: Фев. 21, 2024

Tricomponent cobalt(salen)-catalyzed carbofunctionalization of unsaturated substrates by radical-polar crossover has the potential to streamline access broad classes heteroatom-functionalized synthetic targets, yet reaction platform remained elusive, despite well-developed analogous hydrofunctionalizations mediated high-valent alkylcobalt intermediates. We report herein development a cobalt(salen) catalytic system that enables carbofunctionalization. The entails tricomponent decarboxylative 1,4-carboamination dienes and provides direct route aromatic allylic amines obviating preformed allylation reagents protection oxidation-sensitive amines. merges acridine photocatalysis with regioselective 1,4-carbofunctionalization facilitates radical polar phases coupling process, revealing critical roles reactants, as well ligand effects nature formal species on chemo- regioselectivity.

Язык: Английский

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